Device for making concrete test samples



June 10, 1930. c. s. HOWE 1,752,440

DEVICE FDR MAKING CONCRETE TEST SAMPLES Filed July 29, 1927 Patented June 10, 1930 UNITED STATES PATENT OFFICE CHARLES S. HOWE, F LOS ANGELES, CALIFORNIA, ASSIGNOR TO LOS ANGELES TESTING LABORATORY, OF LOS ANGELES, CALIFORNIA, A CORPORATION OF CALIFORNIA DEVICE FOR MAKING CONCRETE TEST SAMPLES Application filed July 29,

This invention relates to improvements in a device for making concrete test samples, and

refers more particularly to a convenientform into which the concrete mix is placed and permitted to set, after which the form is removed and the sample tested.

The important object of the invention lies in the convenient method of removing the form after the concrete mix has set in the form. 4

Fig. 1 is a side elevational view of the form.

Fig. 2 is a top view of the form shown in Fig. 1.

Fig, 3 is a view taken along the line 33 in Fig. 1.

Fig. 4 is a modified type of construction in which the side plates are ofiset as compared with the construction shown in Fig. 3.

Referring to the drawings, the form com- 7 2o prises a sheet of metal 1, rolled or bent into cylindrical or other shapes and being cut longitudinally in order that the form may be drawn together in the form of a cylinder or other shapes or spread to increase its diameter when the form is to be removed from the concrete sample. Along the edges of the longitudinal slit are welded, riveted or otherwise fastened, slide plates 2 which have upturned portions adapted to be engaged by a locking bar 3 which has its edges crimped slightly more than 90 and shown at 3. These turned down edges form the engaging sides of the locking bar which slides along the upturned portions of the flanges or slide plates and which serves to draw together the form to produce a cylindrical or other shaped molds.

Over the top of the locking bar is a cover plate 4 which prevents the mix from filling in the space between the slide plates and the locking bar, thereby increasing the difiiculty of sliding the lock bar from the mold when the form is removed from the sample. A handle 5 is positioned on the outside surface of the locking bar to assist in the manipulation of the operation of the form.

In actual practice the locking bar is fitted onto the slide plates or slide flanges and the mold or form set upright and a concrete mix shoveled into the form. The mix is then per- 1927. Serial No. 209,280.

mitted to set, at which time the locking bar may be slid from engagement with the form and the form springs away from the concrete material and is removed.

Concrete material plays such an important part in modern constructions that the testing of samples, as the work progresses, becomes more and more an essential part of the su perintending engineers work. The method of securing the proper samples for tests has, however, heretotore been a source of great mconvenience.

In Fig. 4 I show another form of slit where one edge extends over to obtain support from the slide plate 2. This provides additional strength and rigidity and procures a better sample of the molded material.

While the form has been described as a cylindrical form, it will be understood that a square, hexagonal, octagonal or other suitable shaped form may be used in which the fastening means of the type shown is employed.

I claim as my invention:

1. A form for making concrete test samples, comprising a cylindrical tube cut longitudinally, slide plates 011 the edges of the longitudinal cut. a slidable locking means adapted to engage the slide plates and hold the edges of the form together, said locking means closed at one end.

2. A form for making concrete test samples, comprising a resilent, metallic, onepiece, cylindrical tube cut longitudinally and rolled to a greater diameter than the loaded form will assume, slide plates offset from the edges of the longitudinal cut and arranged substantially parallel thereto and set at an angle of less than 90 to the surface of the form, and slidable locking means closed at one end adapted to continuously engage the slide plates throughout their length and hold the abutting shoulders oi the form together.

CHARLES S. HOlVE. 

